The Carnegie Supernova Project: The Low-Redshift Survey

Supernovae are essential to understanding the chemical evolution of the Universe. Type Ia supernovae also provide the most powerful observational tool currently available for studying the expansion history of the Universe and the nature of dark energy. Our basic knowledge of supernovae comes from the study of their photometric and spectroscopic properties. However, the presently available data sets of optical and near-infrared light curves of supernovae are rather small and/or heterogeneous, and employ photometric systems that are poorly characterized. Similarly, there are relatively few supernovae whose spectral evolution has been well sampled, both in wavelength and phase, with precise spectrophotometric observations. The low-redshift portion of the Carnegie Supernova Project (CSP) seeks to remedy this situation by providing photometry and spectrophotometry of a large sample of supernovae taken on telescope/filter/detector systems that are well understood and well characterized. During a five-year program which began in September 2004, we expect to obtain high-precision u'g'r'i'BVYJHKs light curves and optical spectrophotometry for about 250 supernovae of all types. In this paper we provide a detailed description of the CSP survey observing and data reduction methodology. In addition, we present preliminary photometry and spectra obtained for a few representative supernovae during the first observing campaign.Comment: 45 pages, 13 figures, 3 tables, accepted by PAS

Dealing with mobility: Understanding access anytime, anywhere

The rapid and accelerating move towards the adoption and use of mobile technologies has increasingly provided people and organisations with the ability to work away from the office and on the move. The new ways of working afforded by these technologies are often characterised in terms of access to information and people ‘anytime, anywhere’. This paper presents a study of mobile workers that highlights different facets of access to remote people and information, and different facets of anytime, anywhere. Four key factors in mobile work are identified from the study: the role of planning, working in ‘dead time’, accessing remote technological and informational resources, and monitoring the activities of remote colleagues. By reflecting on these issues, we can better understand the role of technology and artefact use in mobile work and identify the opportunities for the development of appropriate technological solutions to support mobile workers

Decoherence of electron spin qubits in Si-based quantum computers

Direct phonon spin-lattice relaxation of an electron qubit bound by a donor impurity or quantum dot in SiGe heterostructures is investigated. The aim is to evaluate the importance of decoherence from this mechanism in several important solid-state quantum computer designs operating at low temperatures. We calculate the relaxation rate $1/T_1$ as a function of [100] uniaxial strain, temperature, magnetic field, and silicon/germanium content for Si:P bound electrons. The quantum dot potential is much smoother, leading to smaller splittings of the valley degeneracies. We have estimated these splittings in order to obtain upper bounds for the relaxation rate. In general, we find that the relaxation rate is strongly decreased by uniaxial compressive strain in a SiGe-Si-SiGe quantum well, making this strain an important positive design feature. Ge in high concentrations (particularly over 85%) increases the rate, making Si-rich materials preferable. We conclude that SiGe bound electron qubits must meet certain conditions to minimize decoherence but that spin-phonon relaxation does not rule out the solid-state implementation of error-tolerant quantum computing.Comment: 8 figures. To appear in PRB-July 2002. Revisions include: some references added/corrected, several typos fixed, a few things clarified. Nothing dramati

Sustained inhibition of progressive joint damage with rituximab plus methotrexate in early active rheumatoid arthritis: 2-year results from the randomised controlled trial IMAGE

Background In the IMAGE study, rituximab plus methotrexate (MTX) inhibited joint damage and improved clinical outcomes at 1 year in MTX-naive patients with early active rheumatoid arthritis. Objective The aim of this study was to assess joint damage progression and clinical outcomes over 2 years. Methods Patients (n=755) were randomised to receive rituximab 2x500 mg+MTX, 2x1000 mg+MTX or placebo+MTX. The placebo-controlled period continued to week 104. Two-year end points were defined as secondary or exploratory and included change in total Genant-modified Sharp score (mTSS), total erosion score and joint space narrowing score from baseline to week 104. Clinical efficacy and physical function end points were also assessed. Results At 2 years, rituximab 2x1000 mg+MTX maintained inhibition of progressive joint damage versus MTX alone (mTSS change 0.41 vs 1.95; p <0.0001 (79% inhibition)), and a higher proportion of patients receiving rituximab 2x1000 mg+MTX had no radiographic progression over 2 years compared with those receiving MTX alone (57% vs 37%; p <0.0001). Contrary to 1-year results, exploratory analysis of rituximab 2x500 mg+MTX at 2 years showed that progressive joint damage was slowed by similar to 61% versus placebo+MTX (mTSS, exploratory p=0.0041). Improvements in clinical signs and symptoms and physical function seen after 1 year in rituximab-treated patients versus those receiving placebo were maintained at year 2. Safety profiles were similar between groups. Conclusions Treatment with rituximab 2x1000 mg+MTX was associated with sustained improvements in radiographic, clinical and functional outcomes over 2 year

Prospectus, October 25, 1984

NICARAGUAN ISSUES PRESENTED; How important is one vote?; Republicans believe their policies are best; Dear Prospectus staff; Democrats believe they have the answers; Busing of private school students Who will foot the bill?; Library director\u27s son honored Johnson is All-American; Library undergoes computerization; PC Happenings; Women\u27s workshop turns to life choices; Family program offered in 4 parts; Health professionals workshop set; Board considers program additions; The Bowling Pin; Wife abuse still widespread problem; Did you know...TV Trivia; Gammon designs for bazaar; International students plan Halloween party; Block talented in diverse fields; Creative Corner...Especially for you!!; Doom Story-the climax draws near; Nuclear Weapons Freeze; Rejoice the Poet; Sacred Love; The Little Red Dog; The Unopened Gate; One More Time; The Run; RS 1981-82; Decisions; Watching; The Widower; Classifieds; Farrah can act; The Burning Bed alters opinions; Tina\u27s hot as a solo; Joan\u27s newest lacks punch; Why is Harry so much trouble; Furs possess unique style; Motherhood makes humorous reading; Budget bin; Lady Cobras compile 7-1 record in tournament; Clifton, Sullivan guest on Cobra Rap show; Gold defeat Green in 4 games; Peterson to nationalshttps://spark.parkland.edu/prospectus_1984/1007/thumbnail.jp

Higher urine 1-hydroxy pyrene glucuronide (1-OHPG) is associated with tobacco smoke exposure and drinking maté in healthy subjects from Rio Grande do Sul, Brazil

BACKGROUND: The highest rates of esophageal squamous cell carcinoma (ESCC) in Brazil occur in Rio Grande do Sul, the most southern state, which has incidence rates of 20.4/100,000/year for men and 6.5/100,000/year for women. Exposure to carcinogenic polycyclic aromatic hydrocarbons (PAHs) through tobacco smoke and other sources may increase the risk of ESCC. The aims of the current study were to investigate the degree and sources of PAH exposure of the inhabitants of this region of southern Brazil. METHODS: Two hundred healthy adults (half smokers, half non smokers, half male and half female) were recruited, given a standardized questionnaire, and asked to provide a urine sample for measurement of 1-hydroxypyrene glucuronide (1-OHPG), a PAH metabolite). Urine 1-OHPG concentrations were measured using immunoaffinity chromatography and synchronous fluorescence spectroscopy and urine cotinine was measured using a dipstick test. We examined factors associated with 1-OHPG concentration using Wilcoxon tests and multiple linear regression. RESULTS: Urine 1-hydroxypyrene glucuronide (1-OHPG) was successfully measured on 199 subjects. The median (interquartile range) of urine 1-OHPG in the 199 participants was 2.09 pmol/mL (0.51, 5.84). Tobacco smoke exposure and maté drinking were statistically significantly associated with higher urine 1-OHPG concentrations in the multivariate linear regression model. CONCLUSION: Tobacco smoke and maté both contribute to high levels of benzo[a]pyrene exposure in the people of southern Brazil. This high PAH exposure may contribute to the high rates of ESCC observed in this population. The increased urine 1-OHPG concentrations associated with maté suggest that contaminants, not just thermal injury, may help explain the increased risk of ESCC previously reported for maté consumption